Method for operating a light assistance system

Abstract

The invention relates to a method for operating a light assistant system of a vehicle (1), which has a camera (2) for detecting oncoming or preceding road users and is equipped with means for recognizing an urban environment, wherein the opening of the high beam is suppressed when driving in the urban environment. The method according to the invention is characterized in that an error message relating to a restricted field of view of the camera (2) is suppressed when driving in the urban environment.

Description

Technical Field

[0001] The present invention relates to a method for a lighting assistance system for operating a vehicle, the type of which is defined in more detail in the preamble of claim 1. Background Technology

[0002] Lighting assistance systems for vehicles are known in the prior art. They are sometimes described using the English name Intelligent Headlight Control (IHC). At their core, they always include a camera, typically pointing forward in the direction of travel, which identifies oncoming and forward road users and excludes them from the high beam distribution of the vehicle. This can be achieved, for example, by simply switching from high beams to so-called low beams, or in more complex lighting systems, by selectively eliminating glare for road users by creating "gaps" in the high beam distribution, such as areas that should not glare oncoming road users.

[0003] Furthermore, such lighting assistance systems typically operate such that the high-beam assist device is used only on rural roads, highways, etc., while in urban environments (i.e., in urban traffic), the high-beam assist device remains off when driving through villages, settlements, industrial areas, etc. In this context, reference can be made, for example, to DE 10 2009 028 342 A1, which describes a method and apparatus for activating a vehicle's urban lights based on an identified environment. Here, within the aforementioned meaning, "urban lights" refers to the deactivation of the high beams in the lighting assistance device. In the case of the aforementioned document, to identify the urban environment, road lighting units are detected, and the spatial distance between these road lighting units is used to determine whether the vehicle is in an urban environment. Other methods for determining the urban environment—such as based on the ambient lighting level or based on the vehicle's satellite navigation coordinates and comparison with a corresponding map—are also known from other existing technologies.

[0004] In practice, it may happen that the vehicle's environmental sensors, while functional, are blocked, for example, by dirt. These sensors then become unusable for their intended purpose. In this context, as an example only, see DE 10 2018 220 114 A1 or its essentially corresponding DE 10 2018 220 113 A1. In these documents, other general prior art descriptions indicate that such obstructions can be identified based on the vehicle's movement pattern.

[0005] In practice, sensor malfunctions related to the lighting assistance system may include, for example, a limited field of view for the camera, particularly due to dirt, heavy rain, or fogging of the window glass through which the camera views. This can lead to the generation of an error message informing the driver that the lighting assistance system is temporarily unavailable. Summary of the Invention

[0006] The object of this invention is to provide an improved method for operating the lighting assistance system according to the preamble of claim 1, which reduces unnecessary error message displays.

[0007] According to the invention, this objective is achieved by a method for operating a lighting assist system having the features of claim 1, and particularly the characterizing portion of claim 1. Advantageous designs and improvements of the method according to the invention are given in the dependent claims subordinate to this independent claim.

[0008] In the method according to the invention, error messages related to limited camera field of view that may occur when driving in urban environments are suppressed. As explained above, in such lighting assistance systems, the urban environment must typically be identified in one and / or another way. The lighting assistance system thus knows that it is in an urban environment and does not require high beams; the assistance system is responsible for turning the high beams on and / or off and, if necessary, eliminating glare to oncoming or forward road users. In urban environments, it is preferable to always drive with low beams.

[0009] However, many vehicle users are now increasingly using headlight assist systems in urban environments. Here, particularly in autumn and winter, the inside of the windshield fogs up relatively quickly in the correspondingly lower temperatures and when the vehicle is stationary, due to moisture from the vehicle depositing on the typically cooler glass. Many cameras, primarily used for headlight assist systems and possibly for other purposes, are mounted in the upper front section of the windshield and pointed forward in the direction of travel. If the windshield fogs up, the cameras' field of view is limited. The same applies if this upper section of the windshield is still covered in ice, or if ice / snow residue in this area wasn't properly cleared before departure, and the driver typically doesn't look through this section. This leads to situations where, when starting a journey in a dark urban environment, the headlight assist system is activated first, and then the camera's field of view is obstructed or limited. However, in practice, this is irrelevant in urban environments because low beams are used anyway, and the assist system doesn't utilize high beams for switching on and off to the intended extent.

[0010] In this situation, the method according to the invention precisely suppresses error messages regarding limited camera field of view, which have no impact on the actual use of the vehicle. Thus, the driver is freed from unnecessary messages and can therefore focus better on the traffic situation rather than on corresponding messages displayed on the instrument cluster such as "High beam assist is disabled due to obstructed camera field of view." The method according to the invention suppresses error messages including limited camera field of view even when they are detected anyway and are not needed.

[0011] Another highly advantageous design of the method according to the invention is that, if the error message regarding the limited field of view of the camera still exists after leaving the urban environment, the error message is displayed again after a specified period of time from the time of leaving the urban environment.

[0012] This advantageous improvement of the method according to the invention ensures that, when leaving the urban environment, if the error message is still up-to-date—for example, if the windshield is still fogged—it is displayed to inform the driver that high beams are a useful aid in this situation. Preferably, a specified time period is waited before displaying the error message, partly to avoid immediately "surpriseing" the driver with the error message at the city's edge, and partly to ensure that when driving in the outskirts of the city, the error message is not unnecessarily displayed when the vehicle may return to the city in a very short time.

[0013] Another highly advantageous design feature of this idea is that the vehicle driver can actively change the specified time period. Therefore, after leaving the city, the suppression of warning messages can be influenced by the vehicle user in terms of time period; for example, the user can automatically configure a preferred time period through a menu system, adjusting the vehicle and the possible display or suppression of such error messages according to individual needs.

[0014] As already mentioned, this method can be particularly meaningful when used with a camera positioned behind the windshield, its view extending through the windshield towards the direction of travel, for a lighting assistance system. However, this method can also be used with other cameras, such as those in external areas where their field of view may be obstructed by snow, ice, or high humidity.

[0015] Here, devices for identifying urban environments can, in particular, utilize road lighting identified by environmental sensors, brightness detected by sensors, driving speed, and a comparison between the vehicle's position determined by satellite navigation and a map displaying the urban environment to determine whether the vehicle is in an urban environment. In particular, these options can also be combined to enable the identification of urban environments with the greatest possible reliability.

[0016] According to a very advantageous extension scheme, the urban environment can be determined based on road lighting, that is, by calculating the number of identified streetlights and then inferring the urban environment by referring to a specified number of streetlights (in particular, a specified number of streetlights per distance unit).

[0017] In this method, streetlights are counted and evaluated as a total number or a quantity per unit distance. If a certain number is exceeded, an urban environment is inferred. Additionally, this can be used, for example, in conjunction with brightness sensors to identify both urban environments and daylight at specific brightness values, and to operate the lighting assistance system in urban environment mode or deactivate it accordingly during the day. As a further supplement, the location of vehicles can also be determined, particularly to verify the results identified by vehicle sensors. Attached Figure Description

[0018] Other advantageous designs of the method according to the invention are also given by way of embodiments described in more detail below with reference to the accompanying drawings.

[0019] In the attached diagram:

[0020] Figure 1 A schematic diagram is shown of a vehicle equipped with a camera in an urban environment identified by the camera; and

[0021] Figure 2 A flowchart illustrating a possible design scheme for the method according to the present invention is shown. Detailed Implementation

[0022] exist Figure 1 The illustration shows a vehicle labeled 1, which is equipped with a multi-function camera 2, as indicated schematically. This multi-function camera serves two purposes: capturing the surrounding environment of vehicle 1 and also functioning as a so-called lighting assistance system.

[0023] exist Figure 1In the scenario shown, three streetlights, marked with reference numeral 3, are schematically indicated on the edge of the road on which the vehicle is traveling. These streetlights are located within the field of view of the camera marked with reference numeral 4 and are accordingly identified by the multi-function camera through a computing unit located inside or possibly outside of the multi-function camera 2. If a certain number of streetlights are present, it is concluded that the vehicle is in an urban environment.

[0024] These or other possibilities for identifying urban environments can now be used in ways known per se for lighting assistance systems. In urban environments, lighting assistance systems are limited to so-called low beams, and in non-urban environments, high beams are used accordingly. The lighting assistance system turns the high beams on and off as needed, or actively eliminates glare for road users traveling in front or oncoming, for example, by eliminating glare for individual road users if pixel headlights or other suitable methods that affect light distribution are used.

[0025] Figure 2 The diagram illustrates the basic process flow, with the known components of the lighting assistance system primarily shown in the lower right area. This will be explained in more detail below.

[0026] and Figure 1 Unlike the schematic diagram, the multi-function camera 2 is typically positioned behind the windshield of vehicle 1 and looks forward in the direction of travel F. If the windshield fogs up or if the upper area viewed by the multi-function camera 2 through the windshield is not completely cleared of ice and snow, the field of view of the multi-function camera 2 will be obstructed. In this case, an error message is generated in the system according to the prior art; however, this in some cases only unnecessarily agitates the driver of vehicle 1 and distracts their attention from traffic conditions.

[0027] Therefore, the proposed method stipulates that after activating the lighting assist system in the first step (marked by reference numeral S100), step S101 queries whether the field of view of the multi-function camera 2 is obstructed. If not obstructed, the lighting assist system operates normally. As mentioned at the beginning of this document, this requires identifying whether the vehicle 1 is in an urban environment. This is accomplished by querying in step S102. If the vehicle is in an urban environment, in step S103, operation is achieved using only low beams and the method jumps back to the beginning and repeats the corresponding steps. If the vehicle has now left the urban area or the lighting assist system is activated outside the urban area, step S104 is executed instead of step S103, in which the high beams are activated, i.e., the lighting assist system is actively used as a high beam assist. As mentioned above, steps S102 to S104 are, in principle, the same parts as in the implementation of conventional lighting assist systems, wherein querying step S102 is necessary in all cases to distinguish whether to operate with low beams according to step S103 or with high beams according to step S104.

[0028] When visibility is correspondingly obstructed, the method according to the invention is used. This typically results in an error message, regardless of whether other existing lighting assistance systems are used. According to the invention, in the branch where the inquiry in step S101 receives an affirmative answer, the question of whether vehicle 1 is in an urban environment is now also asked. This step is here labeled S202 and uses the data already available in step S102. If not in an urban environment, i.e., if the vehicle is outside of an urban environment, an error message known in itself is generated in step S204 (e.g., high beam assist is unavailable due to obstructed visibility of camera 2), and this error message is displayed to the driver of vehicle 1, for example, on the multifunction display of vehicle 1. However, vehicle 1 is often in an urban environment, as vehicle 1 is likely to begin its journey in an urban environment, and the problem of window fogging usually occurs at the beginning of the journey. In this case, the process jumps directly to step S203 after the inquiry in step S202, i.e., activating the low beam headlights, which is meaningful in an urban environment. In the method according to the invention, error messages are omitted or actively suppressed. Thus, the driver of vehicle 1 is not burdened by unnecessary error messages in this situation and may be distracted from road conditions.

[0029] Here, similar to step S204, this method also jumps back to the query in step S101, so that it can not only respond to the changing situation of the camera field of view being blocked in step S101, but also respond to situations such as leaving the urban environment in step S102 or S202.

Claims

1. Method for operating a light assistant system of a vehicle (1), which vehicle has a camera (2) for detecting oncoming or preceding road users and is equipped with means for recognizing an urban environment, wherein the opening of the high beam is suppressed when driving in an urban environment, characterized in that an error message relating to a restricted field of view of the camera (2) is suppressed when driving in an urban environment; the error message is displayed again after a specified period of time after leaving the urban environment, if the vehicle (1) has left the urban environment and the error message relating to the restricted field of view of the camera (2) is still present.

2. Method according to claim 1, characterized in that the specified period of time can be actively changed by the user of the vehicle (1).

3. Method according to claim 1 or 2, characterized in that a camera (2) arranged behind the windshield of the vehicle (1) and looking through the windshield in the direction of travel (F) is used for the light assistant system.

4. Method according to claim 1 or 2, characterized in that the means for recognizing an urban environment evaluate at least the road lighting, the brightness, the vehicle speed of travel, and / or the position of the vehicle (1) relative to a map of the urban environment detected by a satellite navigation system, or a combination of the above.

5. Method according to claim 4, characterized in that the urban environment is determined from the road lighting, wherein the number of recognized street lamps (3) is calculated, and an urban environment is inferred once a specified absolute number of street lamps (3) or a specified number of street lamps (3) per distance unit is exceeded. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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